This invention pertains to the art of tailgates and more particularly to sealable tailgates.
This invention is particularly applicable to sealable tailgates of large containers of the type used for transporting hazardous waste, such as dump trailers, and will be described with particular reference thereto. However, it will be appreciated that the invention has broader application and may be advantageously employed in other environments.
Tailgates of the type to which this invention pertains are typically components of large containers and trailers used for transporting waste materials, specifically hazardous waste materials. The nature of these materials, necessitates that the tailgates be capable of being properly sealed. However, previous attempts to seal these tailgates have proven somewhat ineffective.
In the past, the typical tailgate was sealed by affixing rubber strips around the frame of the tailgate opening. When the tailgate was closed, the rubber was expected to provide a sufficient seal for the container and prevent materials from seeping out. However, the simple rubber seal proved to be ineffective for a variety of reasons. It was normally positioned in such a way that it was continually exposed about the frame when the tailgate was open. Material that was discharged through the opening flowed directly over the rubber and eventually caused portions of the rubber to be worn away. This wearing away diminished the seal's effectiveness, and substantial leaks developed around the tailgate. Notably, however, the wearing away of the rubber was not the only factor which caused the tailgate to leak.
As the loaded containers were transported by trucks along the highways, the materials inside, typically either fluids or slurries, were forced against the tailgate. In time, the tailgate became distorted and bowed outwardly. This distortion forced the periphery of the tailgate to lose its snug fit over the rubber seal. In effect, the worn rubber seal, coupled with the distorted tailgate, dangerously allowed transported materials, even hazardous waste materials, to leak from the tailgate. Both the rubber seal and the tailgate had to be replaced continually. Although these constant replacements provided a temporary solution to the leakage problem, they did not prove economically feasible Instead, the entire situation presented substantial difficulties with respect to safe and economical transportation of hazardous wastes to designated waste depositories. In order to overcome these difficulties, it became desirable to develop an economical tailgates seal that does not rapidly wear out and that does not require continuous replacement. Further, it became desirable to develop a tailgate that is restrained from being distorted about its periphery.
The present invention contemplates a new and improved arrangement which overcomes all of the above-described problems and others to provide a tailgate assembly wherein a seal is situated and arranged so that it will not be worn out by the passage of material through the tailgate opening. Because this seal is in a protected position, it does not have to be continually replaced, and provides an economical means for sealing the tailgate. Additionally, the present invention discloses a peripherally reinforced tailgate which will prevent distortion and reduce the likelihood that hazardous materials will leak from the container.